Sparking plug



y 1938. s. RUTHARDT 2,117,216

SPARKING PLUG 7 Filed Sept. 25. 19:55

4W3 Jab- W Patented May 1c, 1933 PATENT OFFICE sranma PLUG .Gnstav Buthardt, Stnttgart-Znflenhausen,

Germany UNITED STATES f Application September :5. ms, mm. mm

In Germany October 8, 1932 1 cum. .(c 123-109,

- This invention relates to spark plugs with a hollow body defining a central longitudinal passage for the reception 0! a central electrode and tips. and with inwardly extending projections 5 which subdivide the passage into a plurality of 1 combustion chambers of alternately increasing and decreasing cross-sectional area, for ellecting a more thorough churning, and consequently amore complete combustion of the mixture in the It is an object of the; invention to provide an improved spark plug of this type. To this end a helical groove walls of.the combustion chambers.

The helically shaped grooves in the double conical combustion chambers impart to the jet of burning gases the direction of a spreading or,

point flame after the ignition oi the mixture.

The sparking plug is intended to ensure a smooth running-oi the engine tree from knockm ing, even when employing a'so-called poor mixture. Even in the case or high compression engines the spark plug can be employed with inferior fuel mixtures, such as gas oil, spirit mixtures and the like, without detrimentally ailect-.

ing the output and the life of the engine.

An embodiment'o! the invention is illustrated.

is made in the upper end of a screw-threaded extension portion.

The ends of the tips 0 are bent into the combustion chamber surrounding the central eiectrode c. I

I claim:--'

A sparking plug for internal combustion engines, comprising in combination a hollow sparking plug body, mass-electrodes and a central electrode in said body, said body having a passage extending to said electrodes and composed of a plurality of alternate conically widening andnarrowing sections, and having a helical groove formed in the conically widening and narrowing sections of the passage. 3|

ous'rav Rum. 

